Automobile expansion tank cover detection device

The utility model relates to the technical field of automobile expansion tank covers, in particular to an automobile expansion tank cover detection device, and solves the problem that the suitability of a positioning mechanism of an automobile expansion tank cover detection device in the prior art needs to be improved. An automobile expansion tank cover detection device comprises a rack, a rubber pressure head driven and controlled by an air cylinder and a pressurization mechanism, and further comprises a clamping mechanism, the clamping mechanism comprises a fixed seat installed on a workbench of the rack, and the cross section of the fixed seat is of a circular structure. Before the automobile expansion box cover is detected, the expansion box cover is placed on the top of the fixing seat, then the threaded sleeve is rotated to enable the extrusion sleeve to move upwards so as to push the abutting plates in the annular array to move in the radial direction, and therefore automatic center positioning of the